Dampened railway car truck

ABSTRACT

A railway train having articulated vehicle bodies. A steering beam spans across each two adjacent vehicle bodies. Each beam is vertically pivoted or ball-jointed at points along the longitudinal center line of the adjacent vehicle bodies at some distance from the end of each vehicle body. The steering beam acts as a structure to which a suspension unit (bogie truck) is attached. The suspension unit is attached to the beam in a manner which permits the suspension unit to rotate in yaw about a vertical axis. The yaw rotation may be accomplished either freely or against the restraint of springs, viscous dampers or friction devices.

United States Patent Newman et al. [4 1 Oct. 10, 1972 [54] DAMPENEDRAILWAY CAR TRUCK 1,022,054 4/1912 Warner ..105/176X [72 Inventors:Michael Newman; David Boocock, 4/1934 lquckenberg ct aLlQsLU X both ofLondon England 2/1936 Liechty ..105/3 2,081,007 5/1937 Gelssen ..105/176[73] Assignee: British Railways Board, London, 2,792,791 5/1957 Kreissig105/4 R England 2,823,623 2/195 8 Heredia ..-l05/3 Filed: March 19713,133,508 5/1964 Sensemch ..105/4 R [211 P 129,899 PrimaryExaminer-Arthur L. La Point Assistant Examinerl-Ioward Beltran v RelatedUS. Application Data Atmmey SommerS & Young [63] Continuation-impart ofSer. No. 849,322, Aug.

12, 1969, abandoned. [57] ABSTRACT [30] Foreign Application PriorityData A railway train having articulated vehicle bodies. A steering beamspans across each two adjacent vehicle s- 20, 1969 Great Bmam--39,318/68 bodies. Each beam is vertically pivoted or ball-jointed atpoints along the longitudinal center line of the ad- U.S. R, jacent vehile bodies at some distance from the end of 105/175 132 each vehiclebody. The steering beam acts as a struc- 105/199 R, 105/211 ture towhich a suspension unit (bogie truck) is at- [51] Int. Cl .136 3/ 1361fl9'61f 38 tached. The suspension unit is attached to the beam in Fieldof Search 4 4 a manner which permits the suspension unit to rotate105/17], 174, I76, 175 A, 182 R, 199 R, in yaw about a vertical axis.The yaw rotation may be 2ll accomplished either freely or against therestraint of springs, viscous dampers or friction devices. [56]References c'ted 6 Claims, 6 Drawing Figures UNITED STATES PATENTS2,115,095 4/1938 Bugatti ..105/4 R STEER|NG s New 4 BEAMS ea M a a w recmi I a T S w Z b 2 2 tBODYZ 2304 RADIUS PATENTEDBBT 10 I972 SHEET 2 BF 4DAMPENED RAILWAY CAR TRUCK This application is a continuation-in-part ofour U. S.

application Ser. No. 849,322, filed Aug. I2, 1969, and now abandoned.

This invention relates to railway trains and is directed to the problemof steering railway vehicles making up a train round curved track.

The object of the invention is to provide a mechanism for articulatedtrains that (a) provides geometric steering of suspension units (bogietrucks) between vehicles into an attitude substantially tangential tothe track when on curves of constant curvature and (b) permits gross yawmisalignments of the suspension units relative to the vehiclecenterlines so that curves of varying curvature, particularly reversecurves (8- curves), can be negotiated without risk of derailment. 1

. According to this invention a railway train comprises at least twovehicle'bodies articulated at their adjacent ends to restrain relativelateral displacement therebetween but to permit relativeangulardisplacement therebetween, a rigid beam (hereinaftertermed a "steeringbeam connected at its ends to the two vehicle bodies at a distancelongitudinally of the vehicle bodies from their articulated connectionwith each other and in a manner permitting said relative angulardisplacement of said vehicle bodies, and a suspension unit including atleast one wheelset mounted on said beam, the suspension unit beingattached to the steering beam in a manner which permits it to rotate inyaw about a vertical axis.

Preferably said vertical axis passes through the body articulation pointon straight track.

The yaw rotation may be accomplished either freely or against therestraint of springs, viscous-dampers or friction devices.

The invention will now be further explained with the aid of theaccompanying drawings, in which:

FIG. l'shows a schematic plan view of an intermediate vehicle and itstwo adjacent vehicles in a train having a configuration according to theinvention and negotiating a curved track of constant curvature; theradius of curvature of the track related to the length of the vehicleshas been shown much smaller than would be experienced in practice sothat the relative displacements of the vehicle bodies etc. when thetrain is negotiating curved track can be readily appreciated from thedrawings.

FIG. 2 shows a schematic plan view of two of the adjacent vehicles shownin FIG. 1 negotiating a reverse curve.

FIG. 3 is a side elevation of one form of connecting and suspensionarrangement at the adjacent ends of adjacent vehicle bodies of thetrain.

FIG. 4 is a plan view of the arrangement shown in FIG. 3,

' FIG. 5 is a side elevation of a second form of connecting andsuspension arrangement at the adjacent ends of adjacent vehicle bodiesof the train, and

FIG. 6 is a plan view of the arrangement shown in FIG. 5.

ln FIGS. 1 and 2 the vehicle bodies 1, 2 and 3 are represented by theirlongitudinal center lines and the track 4 is represented by its centerline. The vehicle body 1 is articulated to the bodies 2 and 3 at jointsJ.

Extending across each of the joints J between the bodies 1 and 2 andbodies 1 and 3 are steering beams S. Each steering beam S is connectedat points S, and S to the two associated vehicle bodies by pin joints orother means of lateral constraint on the longitudinal center lines ofthe bodies 1, 2 and 3 and which permit the bodies 1, 2 and 3 freely totake up their relative angular position on curved track.

Each of the steering beams S carries a suspension unit in the form of abogie with two wheelsets W, and W the wheelse'ts being of a kind havingtheir axles mounted for rotation in axle boxes and their wheelsconnected for rotation with the axles. Each suspension unit, asdescribed hereinafter with reference toFlGS. 3 to 6, is mounted for yawrotation about'a vertical axis which in straight track passes throughthe articulation points .l. t

Throughout the length of the train up to the leading and last vehiclebodies the arrangement will be similar to that shown in FIGS. 1 and 2;

Referring to FIG. 1, the ratio between the lengths b and b is chosen sothat the steering beam lies substantially tangential to the track atpoint T. Clearly, if the vehicle bodies are of equal lengths so that thevehicle body points of tangency Q, and 0 are at the midlengths of thevehicles, the steering-beam is symmetrical about point T, Le. b, b Thecase where b does not equal b, is considered below. When the vehiclesarticulateas shown in FIG. 1, i.e., when the steering beam istangential, it is evident that the suspensionunit carried by thesteering-beam S is steered into a tangential position without resultantyaw rotation between the suspension unit and the steering beam. Thesteering beam thus acts as a coarse steering mechanism for the axles.Since the two axles are each displaced by distances afrorn the point oftangency T, they are not steered by the steering beam into perfectradial alignment. However, provided the error is small, creep forces(friction forces due to microslip between wheel tread and rail) are,within the limits of adhesion, able to yaw the axles more nearly intothe desired radial alignment against the restraint of primary yawsuspension springs.

Since the triangle S 18 in FIG. 1 varies in size as a function of trackcurvature, relative longitudinal freedom must be incorporated into oneof the joints, 8,, .l, or S Conveniently, joint J is chosen to havelongitudinal freedom, so that the steering beam, can act as a couplingmember between adjacent vehicles, and so transmit traction, braking, andlongitudinal buffing forces down the train.

FIG. 2 shows a schematic plan-view of two vehicles negotiating a reversecurve, the suspension unit being shown as straddling the point ofinflection of the track. In this case, the center lines of two adjacentvehicle bodies may be substantially in line, so that the steering beamcannot be aligned tangential to the track. It follows, however, that thesuspension-unit must rotate in yaw relative to the steering beam byangle ill in order to negotiate the curve. Therefore, the suspensionunit must be pivoted, actually or effectively, at a single point on thesteering beam. Also, the restraint in yaw must not be excessive,otherwise a dangerous tendency to derail may ensue.

Although a two-axled bogie suspension unitis shown in FIGS. 1 and 2, thesuspension unit could equally be single-axled, three-axled, etc.

As mentioned above the lengths b and b, have to be different if thesteering beam S is to take up a tangential attitude on constantcurvature track when the beam is attached to vehicles of dissimilarlengths. Q, and Q are the points along the vehicle bodies which arechosen to be tangential to constant curvature track. Assuming that thetrack center line radius R is very. large compared with the vehicledimensions, we may write, for the steering beam to be tangential atpoint T,

where j and], are the distances shown on FIG. 1.

Therefore, the thro'wover distance TJ may be written as b i /Ro b h/R0Hence, if length b, is specified, from consideration of other factors,length b must be arranged to be I 2 j1 j2 Referring now to FIGS. 3 and4, these show the suspension and interconnecting arrangement at theadjacent ends of two adjacent bodies. For convenience the arrangementwill be considered as that at the adjacent ends of vehicle bodies 1 and2 of FIGS. 1 and 2.

in FIGS. 3 and 4 the articulation joint J is represented by ball joint26, the steering beam S by member 24 and the joints S and S by balljoints 25.

The suspension unit comprises a bogie frame (i.e. a truck frame) 11supported on the axles boxes 12 of wheelsets W, and W via primaryvertical and yaw suspensions represented diagrammatically at 12'. Asecondary frame 33 is connected to .the bogie frame 1 1 by swing links34 providing a lateral suspension. The steering beam 24 is supported onthe secondary frame 33 and hence on the bogie frame by vertical springs35. The weight of the bodies] and 2 is supported-in turn by the steeringbeam 24.

Connected between the bogie frame 11 and the steering beam 24 is a yawsuspension of the relaxation type. In this yaw suspension the bogieframe 11 is connected rigidly in yaw by rods 13 to the cross beam 16pivoted at 40 to the steering beam. This beam 16 is restrained in yaw tothe steering beam by viscous dampers and springs, 22 and 23, in series.Thus the whole bogie pivots against the yaw suspension about thevertical axis provided by pivot 40.

Referring now to FIGS. and 6, this shows an alternative arrangement tothat shown in FIGS. 3 and 4. As far as possible the same referencenumerals have been used for parts having corresponding parts in theFIGS. 3 and 4 arrangement.

A rigid longitudinal steering beam 24 interconnects the two adjacentbodies 1 and 2, the vehicle bodies being connectedto the beam byuniversal joints-25 and interconnected at their adjacent ends by auniversal joint 26. A pair of the transverse beams 16 are pivotallymounted at their centers to the steering beam 24 at each 'end thereof. Apair of load bearing swing arms 13' are'pivotally mounted to the ends ofeach of the beams 16 and connect to a respective end frame 11' each endframe carrying a wheelset. A pair of combined dampers and springs 22/23are connected between the beams 16 and the beam 24 as shown in FIG. 6.

An intermediate frame 27 is arranged between the two end frames 1 1' andis supported on the end frames 11', being connected thereto at each endby a pair of vertical'links 28 provided ,with a ball joint 29 at eachend. A transverse tie rod 30 or some other device is connected betweeneach end frame 11' and a longitudinal extension 31 of the intermediateframe 27 and restrains lateral movement but allows relative longitudinaland yawing movements between the end frames 11 and the intermediateframe 27. Ball joints 32 are provided at each end of the tie rod 30.Other forms of vertical support which do not restrict relativehorizontal movement between the frame 27 and the frames 1 1 can be used.

A secondary frame 33 is suspended from the side members of intermediateframe 27 by way of transverse swing links 34 or other lateral suspensionwhich allow only transverse relative movement between the secondaryframe 33 and the intermediate frame 27 A vertical spring 35 is arrangedbetween the secondary frame 33 and the steering beam 24. This spring 35provides the main vertical springing for the vehicle.

The secondary frame 33 is restrained relative to the steering beam 24for example by means of tie rods or guides (not shown) to allow onlyvertical and yawing motions of the secondary frame, and hence theintermediate frame 27, relative to the steering beam 24. Longitudinaland transverse movements of the secondary frame 33 relative to thesteering beam 24 are prevented by these tie rods. Similarly since theswing links 34 only allow relative transverse movement between thesecondary frame 33 and the intermediate frame 27, the latter is alsoprevented by the tie rods connected between the secondary-frame and thesteering beam, from moving longitudinally relative to the steering beam24.

When the vehicle bodies 18 move sideways relative to the wheelsets in apure lateral motion when the vehicle istravelling on a straight sectionof track, the steering beam 24 also moves laterally and carries thesecondary frame 33 with it by way of the tie rods. The intermediateframe 27 is tied to the two end frames 11' by the lateral tie rods 30and is thus prevented from following this lateral movement of thesecondary frame'33 which thus moves laterally relative to theintermediate frame 27 on its swing links 34. As the beam 24 moveslaterally, the two transverse beams 16 are carried with it and the twopairs of swing arms 13 swing sideways to a position at an angle to thedirection of travel of the vehicle. This sideways movement of the swingarms 13' causes each of the frames 11' to move to a short distancelongitudinally towards the beams 16, away from the intermediate frame27, causing the vertical links 28 to pivot longitudinally of the track,outwardly from the frame 27. The lateral tie rod 30 also pivots relativeto the arm 31 on its joints 32.

One or more dampers (not shown)'are connected for example between thesteering beam 24 and the intermediate frame 27 to damp out these lateralmovements of the vehicle relative to the wheelsets. When the railwayvehicle goes round a curve in the track, the vehicle bodies 1 and 2 andthe steering beam 24 move to take up the position shown in FIG. 1.

If we assume that the vehicle as shown in plan in FIG. 6 is rounding acurve whose center of curvature is towards the bottom of the sheet, thevehicle bodies 1 and 2 and the steering beam 24 will move, relative tothe wheelsets, towards the top of the sheet. The left hand end frame 11will yaw anti-clockwise and the right hand end frame 11' clockwise. Ifthe curve is of constant radius both end frames 11' will yaw, relativeto the steering beam 24 by approximately equal amounts and theintermediate frame 27 will remain substantially unyawed with respect tothe beam 24. The ball joints 29 at the ends of the vertical links 28allow the links 28 to move longitudinally so allowing the end frames 11'to yaw relative to the intermediate frame 27. Each of the end frames 11'is provided with projecting arms 36 on either side of the arm 31 on theintermediate frame 27. Resilient members 37 may be positioned betweenthese arms 36 and each of the arms 31 to control the yawing movements ofthe frames 11' relative to the intermediate frame 27. For yawingmovements greater than a predetermined maximum, one of these resilientmembers 37 will become fully compressed and further yawing movement ofthe wheels'et relative to the intermediate frame 27 will be prevented.In this way excessive yawing motions of the end frames 11 are prevented.

If the radius of the curve is non-uniform, in particular if the curve isa reverse curve (S-curve), gross yaw misalignments must be allowedbetween a longitudinal line joining the wheelset centers and thesteering beam 24. Relative to the beam 24, one frame 11 is displacedlaterally in one direction and the other frame 11' is displaced in theopposite direction. As a result the intermediate frame 27 and thesecondary frame 33 yaw substantially about the central point of the beam24 that is in effect about vertical axis 40. The motions are alsoaccompanied by yawing of the two end frames 11 so that the twotransverse beams 16 are activated by the swing arms 13' to yaw togetherin the same sense. Thus the suspension unit will take up the position ofFIG. 3.

Since yaw movements of these beams 16 may be rapid and lead tosubstantial angular displacements of the beams, a device is incorporatedinto the yaw suspension to ensure that excessive forces are notgenerated which could result in derailment. The yaw suspensioncomprising springs 23 and dampers 22 is fitted with blow-off valves inthe dampers so that pressures are limited to a pre-determined maximum.Similarly, if a spring and friction slide arrangement is used, thebreak-out friction force is set to an acceptable level.

Thus in the arrangement of FlGS. 5 and 6 the rotations in yaw of thesuspension unit are about an effective vertical axis 40, not an actualpivot. This is accomplished by combined in-phase yaw movements of thetwo beams 16 and anti-phase lateral movements of frames ll relative tothe steering-beam. The basis of this suspension unit is the parallellinkage arrangements of beams 16, arms 13', and frames 11'. Animportantfeature of this suspension unit is the facility of frames 11' to yawrelative to each other under the control of springs 37 and links 30, sothat the wheelsets can adopt nearly a radial alignment on curves underthe action of creep forces.

We claim:

1. A railwa train com risi a. at least fin o vehicle bodi e sarticulated at their adjacent ends to restrain relative lateraldisplacement therebetween but to permit relative angular displacementtherebetween.

. a rigid beam connected at its ends to the two vehicle bodies at adistance longitudinally of the vehicle bodies from their articulatedconnection with each other and in a manner'permitting said relativeangular displacement of said vehicle bodies, and

c. a suspension unit including at least two wheelsets,

the suspension unit being attached to said beam in the region of themid-length of said beam in a manner which permits it to yaw relativelyto said beam about a vertical axis between the wheelsets.

2. A railway train according to claim 1, wherein said vertical axispasses through the articulation point of the vehicle bodies, when thevehicle bodies are on straight track.

3. A railway train according to claim 1, wherein said suspension unitcomprises a frame in which are mounted at least two wheelsets,. saidframe being pivotally connected to said rigid beam through a yawsuspension for rotation against the restraint of said yaw suspensionabout said vertical axis. I

4. A railway train as claimed in claim 3, wherein said wheelsets aremounted in said frame through a further yaw suspension permitting arestrained yawing movement of said wheelsets relatively to said frame.

5. A railway train as claimed in claim 1, wherein said suspension unitcomprises an intermediate frame connected to said steering beam througha lateral suspension arrangement, a first end frame carrying a firstwheelset and connected at one end'to one end of the intermediate frameand at its other end to said beam through a yaw suspension so that itcan yaw relatively to said beam and the intermediate frame and a secondend frame connected at one end to the other end of said intermediateframe and at its other end to said beam through a yaw suspension so thatit can yaw relatively to said beam and the intermediate frame, saidintermediate frame being connected to said end frames so that it isrestrained from lateral movement relative to said end frames.

6. A railway train comprising:

a. at least two vehicle bodies articulated at their adjacent ends torestrain relative lateral displacement therebetween but to permitrelative angular displacement therebetween,

a rigid beam connected at its ends to the two vehicle bodies at adistance longitudinally of the vehicle bodies from their articulatedconnection with each other and in a manner permitting said relativeangular displacement of said vehicle bodies,

c. at least two wheelsets located in the region of the mid-length ofsaid beam, and

. a yaw suspension through which said wheelsets are mounted to said beamand which restrains said wheelsets against angular movements in ahorizontal plane.

1. A railway train comprising: a. at least two vehicle bodiesarticulated at their adjacent ends to restrain relative lateraldisplacement therebetween but to permit relative angular displacementtherebetween. b. a rigid beam connected at its ends to the two vehiclebodies at a distance longitudinally of the vehicle bodies from theirarticulated connection with each other and in a manner permitting saidrelative angular displacement of said vehicle bodies, and c. asuspension unit including at least two wheelsets, the suspension unitbeing attached to said beam in the region of the mid-length of said beamin a manner which permits it to yaw relatively to said beam about avertical axis between the wheelsets.
 2. A railway train according toclaim 1, wherein said vertical axis passes through the articulationpoint of the vehicle bodies, when the vehicle bodies are on straighttrack.
 3. A railway train according to claim 1, wherein said suspensionunit comprises a frame in which are mounted at least two wheelsets, saidframe being pivotally connected to said rigid beam through a yawsuspension for rotation against the restraint of said yaw suspensionabout said vertical axis.
 4. A railway train as claimed in claim 3,wherein said wheelsets are mounted in said frame through a further yawsuspension permitting a restrained yawing movement of said wheelsetsrelatively to said frame.
 5. A railway train as claimed in claim 1,wherein said suspension unit comprises an intermediate frame connectedto said steering beam through a lateral suspension arrangement, a firstend frame carrying a first wheelset and connected at one end to one endOf the intermediate frame and at its other end to said beam through ayaw suspension so that it can yaw relatively to said beam and theintermediate frame and a second end frame connected at one end to theother end of said intermediate frame and at its other end to said beamthrough a yaw suspension so that it can yaw relatively to said beam andthe intermediate frame, said intermediate frame being connected to saidend frames so that it is restrained from lateral movement relative tosaid end frames.
 6. A railway train comprising: a. at least two vehiclebodies articulated at their adjacent ends to restrain relative lateraldisplacement therebetween but to permit relative angular displacementtherebetween, b. a rigid beam connected at its ends to the two vehiclebodies at a distance longitudinally of the vehicle bodies from theirarticulated connection with each other and in a manner permitting saidrelative angular displacement of said vehicle bodies, c. at least twowheelsets located in the region of the mid-length of said beam, and d. ayaw suspension through which said wheelsets are mounted to said beam andwhich restrains said wheelsets against angular movements in a horizontalplane.